Highly conformal reirradiation in patients with prior oropharyngeal radiation: Clinical efficacy and toxicity outcomes

Abstract

Background: Reirradiation of head and neck cancer is associated with high rates of locoregional failure and potentially severe treatment-related toxicity. We report our institutional experience of reirradiation using modern highly conformal radiotherapy approaches in patients with prior oropharyngeal radiation. Methods: We reviewed patients receiving curative-intent reirradiation with intensity-modulated radiation therapy, stereotactic body radiation therapy, and proton beam radiotherapy at our institution from 1999 to 2019. Disease control, survival, and toxicity rates following reirradiation were determined. Results: Sixty-nine patients were evaluated. Local control (LC), progression-free survival, and overall survival at 2 years following reirradiation were 77%, 35%, and 51%, respectively. Grade 3 or greater (G3+) late toxicities occurred in 46% of patients and 41% required feeding tube placement during or after reirradiation. Conclusions: In select patients with prior oropharyngeal radiation, highly conformal reirradiation offers acceptable LC, but G3+ toxicity and out-of-field failure rates remain high. These findings warrant continued evaluation of new multimodality approaches to improve oncologic outcomes.

Proton Therapy for Head and Neck Cancer: A 12-Year, Single-Institution Experience

“…We have previously detailed patient and treatment characteristics, disease control, and toxicity outcomes for patients treated at our center with PT for oropharyngeal cancer [ 3 , 10 , 12 , 21 – 23 ], skull base tumors [ 24 ], periorbital tumors [ 5 ], nasopharyngeal cancer [ 4 ], adenoid cystic carcinomas [ 6 , 7 ], and paranasal sinus tumors [ 11 ] and for patients treated with PT for reirradiation [ 8 , 9 , 25 ]. Evidence from initial comparative reports in oropharyngeal cancer from our center and others, for example, have demonstrated reduced acute toxicities [ 26 ], reduced weight loss, reduced feeding tube placement [ 22 ], reduced symptom severity during the subacute recovery period [ 21 ], reduced incidence of osteonecrosis [ 23 ], and no difference in overall survival with IMPT compared with IMRT [ 22 ].…”

“…The PSPT plans were generally treated with a sequential, shrinking-field technique, with a daily dose of 2 Gy(RBE), ensuring a field size > 2 × 2 cm. In the reirradiation setting, 66 Gy(RBE) in 33 fractions was generally prescribed in the definitive setting, 60 Gy(RBE) in 30 fractions postoperatively, and target volumes were generally restricted to gross disease or the tumor bed with a margin without reirradiation of elective regions [ 9 ].…”

“…Comparative analyses have established that PT can achieve more optimal dose distributions compared with intensitymodulated radiation (x-ray) therapy (IMRT) for many HNC tumor sites, yet few prospective studies have reported clinical outcomes outside of individual studies reporting on subsites of specific interest [2]. Although we have previously reported our initial clinical experience and patient outcomes after PT for various HNC subsites [3][4][5][6][7][8][9][10][11][12] and a multi-institutional phase III randomized trial of IMPT versus IMRT in oropharyngeal carcinoma (ClinicalTrials.gov identifier: NCT01893307) is ongoing [13], comprehensive reporting of patient outcomes in large HNC cohorts are needed to inform the HNC and PT community.…”

Stereotactic body ablative radiotherapy for reirradiation of small volume head and neck cancers is associated with prolonged survival: Large, single‐institution, modern cohort study

“…In general, the CTV did not include elective nodal coverage. The planning target volume (PTV) was generated with a uniform expansion of 2, 3, and 3.5 mm, respectively, for skull base, mucosal, and neck sites 24 …”

Current Therapeutic Strategies in Patients with Oropharyngeal Squamous Cell Carcinoma: Impact of the Tumor HPV Status

“…(C)RT can be used in patients who did not receive RT before, if salvage surgery is not feasible or as adjuvant therapy after surgical salvage. Reirradiation of previously irradiated tumor sites can be delivered in highly selected cases [93].…”